I've been prowling this forum for the last few weeks, gathing information for a possible move off cable to DirecTV (those upcoming HD stations sound too tempting!). In my pre-HD days, I had a TiVo that I modded with a larger hard drive, giving me a LOT more recording capacity. When I went to a cable DVR, I was stuck with a a maximum of about 20 hours of HD recording capacity. I'd really like to go back to having significantly more than that, so the idea of a large (750Gb-1Tb) external drive on an HR20 sounds alluring. However, I've gotten the idea from some threads that the external drive might get reformatted under certain circumstances, such as rebooting the receiver. Can anybody tell me exactly under what circumstances an external drive might be reformatted (other than on the initial setup, of course)? I'd hate to have a hundred hours of HD tucked away and lose it all because a power outage caused a reboot of my receiver (not to mention the fact that my wife would kill me!). Thanks in advance for any replies!